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Republic of Albania Enterprise Surveys Data Set 1. Introduction This document provides additional information on the data collected in Albania from 13 December 2007 to 24 March 2008 as part of the Enterprise Survey, an initiative of the World Bank. The objective of the Enterprise Surveys is to obtain feedback from enterprises in client countries on the state of the private sector as well as to build a panel of enterprise data that will make it possible to track changes in the business environment over time and allow, for example, impact assessments of reforms. Through interviews with firms in the manufacturing and services sectors, the Enterprise Survey data provides information on the constraints to private sector growth and is used to create statistically significant business environment indicators that are comparable across countries. The report describes the sampling design of the survey, the structure of the dataset and additional information that may be useful when using the data, including information on non-response rates, the calculation of sample weights and country-specific factors that may have affected survey implementation. 2. Sampling Structure The whole population, or the universe, covered in the Enterprise Surveys is the non- agricultural economy. It comprises: all manufacturing sectors according to the ISIC Revision 3.1 group classification (group D), construction sector (group F), services sector (groups G and H), and transport, storage, and communications sector (group I). Note that this population definition excludes the following sectors: financial intermediation (group J), real estate and renting activities (group K, except sub-sector 72, IT, which was added to the population under study), and all public or utilities-sectors. The sample for the Republic of Albania was selected using stratified random sampling, following the methodology explained in the Sampling Manual. Stratified random sampling1 was preferred over simple random sampling for several reasons2: a. To obtain unbiased estimates for different subdivisions of the population with some known level of precision. b. To obtain unbiased estimates for the whole population. The whole population, or universe of the study, is the non-agricultural economy. It comprises: all manufacturing sectors according to the group classification of ISIC Revision 3.1: (group D), construction sector (group F), services sector (groups G and H), and transport, storage, and communications sector (group I). Note that this definition excludes the following 1 A stratified random sample is one obtained by separating the population elements into non-overlapping groups, called strata, and then selecting a simple random sample from each stratum. (Richard L. Scheaffer; Mendenhall, W.; Lyman, R., “Elementary Survey Sampling”, Fifth Edition). 2 Cochran, W., 1977, pp. 89; Lohr, Sharon, 1999, pp. 95 1 sectors: financial intermediation (group J), real estate and renting activities (group K), and all public or utilities-sectors. c. To make sure that the final total sample includes establishments from all different sectors and that it is not concentrated in one or two of industries/sizes/regions. d. To exploit the benefits of stratified sampling where population estimates, in most cases, will be more precise than using a simple random sampling method (i.e., lower standard errors, other things being equal.) e. Stratification may produce a smaller bound on the error of estimation than would be produced by a simple random sample of the same size. This result is particularly true if measurements within strata are homogeneous. f. The cost per observation in the survey may be reduced by stratification of the population elements into convenient groupings. Three levels of stratification were used in this country: firm sector, firm size, and geographic region. The original sample design, with specific targets for these strata, is included in the attached Excel file (Sampling Report.xls.) Industry stratification was designed in the way that follows: the universe was stratified into 1 manufacturing sector (including several industries), 1 services industry -retail-, and one residual sector as defined in the sampling manual. 304 interviews were completed in total, out of an original target of 360 interviews. The main constraint to reach the target interviews was the Universe size and composition, which proved to be smaller than originally expected. Particularly, firms with more than five employees in the Services sector were scarce. Firms from sector 51 (Wholesale) were issued to compensate the shortfall in the Services sector 52 (Retail). The majority of the relevant information, including the accounting data was obtained and entered into the data base. The Productivity section had a high non-response rate on average, reaching between 20 - 25%, depending on the questionnaire. Even if call backs were done to complete the section, the response rate could not be improved by much. Size stratification was defined following the standardized definition used for the Enterprise Surveys: micro (1 to 4 employees), small (5 to 19 employees), medium (20 to 99 employees), and large (more than 99 employees). For stratification purposes, the number of employees was defined on the basis of reported permanent full-time workers. Regional stratification was defined in terms of the geographic regions with the largest commercial presence in the country: Tirana, Durres, Elbasan, Fier, Vlora were the four metropolitan areas selected in Albania. 3. Sampling implementation It was not possible to obtain a usable frame for Albania. Therefore, the design returned to first principles, using a blocks enumeration methodology. Detailed maps of major cities were obtained. These were from aerial mappings projected to a usable scale. They served as the basis of a multi-stage approach. Firstly each city (region) was divided into „blocks‟ and then the blocks were classified into strata defined by the predominant spatial use, 2 using local knowledge. The classifications used for the blocks included industrial, commercial, commercial/residential (mixed), and residential coding. The accuracy of the classification was tested using 30 pilot blocks. That test proved successful. Subsequently another 328 blocks were selected and enumerated; building by building, floor by floor. Each separate unit was identified, classified as to use and in the case of business establishments further details collected as to employee numbers, activity, name, and phone number. This enumeration of a total of 358 blocks was then employed to project to universe totals by reference to the screening results and the number of blocks in each stratum. The establishments enumerated in those blocks were then used as the frame for the selection of a sample with the aim of obtaining interviews at 360 establishments with five or more employees. In addition the World Bank requested interviews at 120 small manufacturing establishments with less than five employees, to be delivered separately as an additional survey. That target was subsequently reduced to 80 as only some 180 small manufacturing establishments had been enumerated. Disproportionate methods were used to reduce the variance of estimates. The quality of the frame was assessed at the onset of the project. The frame proved to be useful though it showed positive rates of non-eligibility, repetition, non-existent units, etc. These problems are typical of establishment surveys, but given the impact these inaccuracies may have on the results, adjustments were needed when computing the appropriate weights for individual observations. The percentage of confirmed non- eligible units as a proportion of the total number of contacts to complete the survey was 6.8% (29 out of 425 establishments). Sample selection was carried out by the TNS team in London using the data obtained from the block enumeration. The selections for Albania were augmented by additional selections from enterprises interviewed during the BEEPS survey in 2005 and a „Large Taxpayers‟ database obtained by the local agency. To reduce non-response bias the samples was drawn in matched replicates so that each sampled establishment had at least one matched substitute (where sample available) in the event of non-contact or refusal. Local Agency team involved in the study: Local Agency Name: IDRA Research & Consulting Country: Albania Membership of international organisation: ESOMAR Activities since: 2001 Name of Project Manager Auron Pasha Name and position of other key Florian Babameto – Coordinator Adela Gjergjani – Fieldwork coordinator persons of the project: Rozeta Koci – Fieldwork coordinator Enton Coka – Data entry and quality control Enumerators involved: Enumerators: 50 enumerators in charge of the blocks enumeration and 50 interviewers in the second phase. Recruiters: the interviewers were also in charge 3 of the recruitment Other staff involved: Fieldwork Coordinators: 2 people Editing: 1 supervisor Data Entry: 4 people Sample Frame: Characteristic of sample frame used: Source: Block Enumeration Sample Frame + Albania’s Large tax payer’s data Base + BEEPS 2005 panel. Year: 2005, 2007 - 2008 Comments on the The retail sector in Albania is mainly composed by small quality of sample companies. This was first noticed when analysing the results frame: from the blocks enumeration and confirmed later during fieldwork. In addition, Manufacturing firms on the ground proved to be fewer than originally estimated prior to the beginning of the survey. From